Democratic congressional candidate Dan McCready is withdrawing his concession in the race to represent North Carolina’s 9th District, telling local station WSOC that he believes his opponent, Mark Harris, knew a contractor for his campaign bankrolled “criminal activity.”

That contractor, McCrae Dowless, is accused of orchestrating widespread election fraud in order to help Harris. Absentee ballots in some areas are unusually — and improbably — tilted toward the Republican.

In a video statement posted to his Twitter account Thursday, McCready said: “I didn’t serve overseas in the Marine Corps just to come back home and watch politicians and career criminals attack our democracy. That’s why today I withdraw my concession to Mark Harris, who’s remained completely silent, and I call on Mark Harris to tell us exactly what he knew, and when he knew it.”

Watch below:

I didn’t serve overseas in the Marines to come home to NC and watch a criminal, bankrolled by my opponent, take away people’s very right to vote. Today I withdraw my concession and call on Mark Harris to end his silence and tell us exactly what he knew, and when. pic.twitter.com/2hcT00DVhQ